The present invention generally relates to implantable electrodes, and more particularly to implantable sensing and stimulating electrodes having reduced post-stimulation polarization.
Following delivery of stimulation (e.g., a cardiac pacing pulse), an electrode surface typically retains an accumulation of charge that persists for a period of time thereafter. This post-stimulation polarization may interfere with subsequent sensing of signals, such as intrinsic cardiac activity signals. This issue has been addressed in a number of ways over the years. One common approach to reducing post-stimulation polarization is to provide a high-surface area coating having a micron or sub-micron sized topography, such as a porous sintered metallic coating, a metal oxide coating, or a coating of platinum black. However, further development in post-stimulation polarization levels is desirable.